News and Perspectives from Pacific Gas and Electric Company

Macroscopic,multicellular, benthicmarinealgae—seaweed to those of you without a Ph.D in marine biology—is a productive source of food (sushi, anyone?), medicinal iodine, alginates used in wound dressings and dental moulds, fertilizer and many other commercial products.

As a ubiquitous and fast-growing “weed,” which clutters our California beaches too much for my liking, kelp may someday have another great use: as a feedstock for renewable biofuels.

Kelp can be converted to fuel one of several ways: by anaerobic digestion; fermenting with yeast to convert their carbohydrates to ethanol; or pyrolysis, a process of heating without oxygen that produces “bio-oil.”

A team of researchers from the University of Illinois recently developed a new strain of yeast that excels at turning red seaweed into biofuels, more than twice as efficiently as previous strains.

Alternative feedstocks grown on land too often compete with food production or have tough fibers that are hard to break down. That makes kelp look all the more attractive.

“Marine ecosystems are an untapped resource that account for over 50% of global biomass and seaweeds themselves are capable of producing more biomass per square metre than fast growing terrestrial plants such as sugar cane,” notes the Society for Experimental Biology.

Research and pilot projects to commercialize kelp for biofuels are advancing in Chile, Scandanavia and Scotland. Seaweed has yet to prove that it is affordable and sustainable enough for mass production, and a 2009 report on the “Potential for Marine Algae as a Source of Biofuel in Ireland” concluded that it was modest at best over the coming decade.